1. Field of the Invention
The present invention relates to an ink jet printer, and, more particularly, to a device for collecting waste ink in an ink jet printer.
2. Description of the Related Art
During printing with an ink jet printer, an ink jet printhead ejects very tiny ink droplets in order to provide the best print quality. The ink droplets are so small that if they do not impact a surface within a short distance of leaving the nozzles, they tend to drift away in a cloud of mist. During the printing of the ejected ink droplets onto a sheet of print medium, such as paper, ink mist drifting is not an issue because the paper is only about 1.00 mm to 1.25 mm away from the printhead. However during an ink spit maintenance operation performed in a maintenance cycle for the printhead, typically there is a much greater distance to cover before the ink reaches the features designed to receive the ejected ink on the maintenance sled. In this empty space, an ink mist cloud can form and float into other areas of the printer. Over time, this ink misting collects on the inside of the covers, some even escaping through holes in the printer covers to form splotches on the outside of the covers.
One attempt to reduce ink misting is to provide a rotating drum in order to give the ink a place to collect. The drum turns so that the ink drips off into an ink well and a clean surface is positioned for the next spit. It is also possible to disable the mechanism for the drum rotation, and to allow the ink to drip around the sides as it collects on the top. In general, however, the drum provides a curved surface, concave down, that the ink strikes and then runs off, to be collected beneath the drum for evaporative dispersion. Such rotating and stationary drums are attached to the maintenance sled.
It is also known to provide the maintenance sled with a chimney into which the spit ink can be directed. The chimney is intended to surround the ink mist cloud and thereby prevent its movement into other areas of the printer. The ink mist collects on the inside walls of the chimney and flows down toward an ink collection area underneath the sled. Such chimneys are affixed to the maintenance sled.
The above-referenced drum and chimney configurations must be designed such that, as the maintenance sled moves upward, the top of the drum or chimney does not physically contact or otherwise interfere with the printhead. Thus, the top of the drum or chimney must be maintained at a distance during the spitting of the printhead that is equal to the vertical distance the sled travels before other maintenance functions are performed, such as capping. A problem with this implementation of the drum or chimney is that with this rather large gap, the mist cloud is not completely captured in the chimney or collected by the drum, and can escape the maintenance area.
What is needed in the art is a device for preventing the drifting of a cloud of ink mist after a spit maintenance operation of an ink jet printhead.
The present invention provides a device for reducing or preventing the drifting of a cloud of ink mist after a spit maintenance operation of an ink jet printhead.
In one form thereof, the invention relates to an ink collection assembly. The ink collection assembly includes an ink collection chimney defined, at least in part, by a tubular structure. The tubular structure has a proximal end and a distal end. The tubular structure extends from the proximal end a first distance to the distal end. The distal end defines an opening for receiving waste ink. A hydrophobic foam is positioned in the tubular structure. With the hydrophobic foam positioned in the tubular structure, the tubular structure includes a hollow portion located between the hydrophobic foam and the proximal end.
In another form thereof, the invention relates to an ink jet printer. The ink jet printer includes a frame and a printhead carrier system coupled to the frame. The printhead carrier system includes a printhead carrier for carrying at least one printhead. An ink collection chimney is defined, at least in part, by a tubular structure, and has a proximal end and a distal end. The proximal end of the tubular structure is coupled to the frame. The tubular structure extends from the proximal end a first distance to the distal end. The distal end defines an opening for receiving waste ink from the at least one printhead. A hydrophobic foam is positioned in the tubular structure. The tubular structure includes a hollow portion located between the hydrophobic foam and the proximal end.